This application claims priority to Japanese Patent No. JP 2000-200861 (IBM Docket No. JP920000147JP1, filed on Jul. 3, 2000, and entitled xe2x80x9cAppearance Inspecting Jig For Small Parts and Inspecting Method Employing the Same Jig.xe2x80x9d
1. Technical Field
The present invention relates to an inspecting jig and an inspecting method that are used in inspecting the appearance of small parts, such as a head assembly, by use of an optical microscope, and more particularly to an inspecting jig and an inspecting method which enable an inspector to inspect many faces of small parts during a single holding operation.
2. Description of the Related Art
A conventional method of inspecting the appearance of small parts, such as a head assembly, by use of an optical microscope will hereinafter be described.
FIG. 18 shows a perspective view of a conventional appearance inspecting method for head assemblies, and FIG. 19 is a diagram showing the image of the visual field of an optical microscope in the conventional appearance inspecting method for head assemblies.
In FIG. 18, reference numeral 103 denotes an objective lens of an optical microscope, 30 a head assembly which is small parts, 150 an empty hand or inspecting glove, and xe2x80x9cPUxe2x80x9d the upper-face image of the head assembly. An appearance inspector for head assemblies inspects the appearance of the head assembly 30 by inspecting the upper-face image PU (see FIG. 19) of the head assembly 30 obtained through the objective lens 103.
FIG. 19 is a diagram showing the image of the visual field of the optical microscope obtained by carrying out the inspection shown in FIG. 18. Reference numeral 31 denotes left wiring, 32 denotes right wiring, 33 denotes a head, 34 denotes a left connecting portion between the left wiring 31 and the head 33, 35 denotes a right connecting portion between the right wiring 32 and the head 33, and 36 denotes a load beam portion.
In the head assembly 30 shown in FIGS. 18 and 19, appearance inspection is unnecessary for the lower face of the head assembly 30, because the wiring 31 and the wiring 32 are in intimate contact on the side of the head 33 of the load beam portion 36. However, there is a need to inspect the connected states of the left and right connecting portions 34, 35 and to inspect the state of the intimate contact of the left and right wirings 31, 32 on the load beam portion 36.
For inspecting the connected states of the left and right connecting portions 34, 35, the direction of the upper-face image PU shown in FIG. 19 is insufficient. The appearance inspector must change, for example, the direction of the head assembly 30 so that as many portions of the connecting portions 34, 35 as possible are visible. More specifically, the appearance inspector has to change the direction of the head assembly 30 so that as many portions of the connecting portions 34, 35 as possible are at the focal position (within the focal depth) of the optical microscope and also on a plane perpendicular to the optical axis of the objective lens 103. In the event the position of the head assembly 30 is improper when inspecting the upper-face image PU, the appearance inspector has to change the position of the head assembly 30.
The direction of the upper-face image PU shown in FIG. 19 is also insufficient in the case of inspecting the state of the intimate contact of the left and right wirings 31, 32 on the load beam portion 36. The appearance inspector must change, for example, the direction of the head assembly 30 so that as many portions of the left and right wirings 31, 32 and the load beam portion 36 as possible are visible. More specifically, the appearance inspector has to inspect the state of the intimate contact of the left wiring 31, by changing the direction of the head assembly 30 so that the entire left wiring 31 is at the focal position (within the focal depth) of the optical microscope and also on a plane perpendicular to the optical axis of the objective lens 103. Then, the appearance inspector has to inspect the state of the intimate contact of the right wiring 32, by changing the direction of the head assembly 30 so that the entire right wiring 32 on the opposite side is on a plane perpendicular to the optical axis of the objective lens 103. In the case where the position of the head assembly 30 is improper at the time of inspecting the upper-face image PU, the appearance inspector has to change the position of the head assembly 30 at the time of inspecting the left wiring 31, and at the time of inspecting the right wiring 32.
In addition, since the head assembly 30 is so small that an optical microscope is required at the time of inspecting the connecting portions and wiring state, it is difficult to execute a suitable holding method wherein the upper-face image PU is inspected in raising the head assembly 30 with an empty hand or inspecting glove 150, then the connecting portions 34, 35 are changed to the direction of inspection, and furthermore, the directions of the left and right wirings 31, 32 are also changed so that they can be inspected.
As described supra, the appearance inspector for the head assembly 30 has to change many times the position of the head assembly 30 in order to inspect the connected states of the left and right connecting portions 34, 35 or the states of the intimate contact of the left and right wirings 31, 32 on the load beam portion 36. Furthermore, the focal point of the microscope must coincide with a position of inspection and each time the holding position is changed.
In the conventional method of inspecting the head assembly 30, as stated above, the appearance inspector for the head assembly 30 inspects the upper face of the head assembly 30, the connected states of the left and right connecting portions 34, 35; and the left and right wirings 31, 32, by changing many times the position of the main body (load beam portion) of the head assembly 30, with the empty hand or the inspecting glove 150, etc., so that the inspection portions of the head assembly 30 are as perpendicular as possible to the optical axis of the objective lens 103, and so that the inspection portions coincide with the focal point of the microscope.
In the above-mentioned conventional appearance inspection of the head assembly 30, however, there is a problem that there are instances where (1) during inspection, the head assembly 30 and the objective lens 103 contact and are damaged, and (2) the static electricity stored in the body of the inspector destroys the head assembly 30 or causes dirt to adhere to the head assembly 30, resulting in a reduction in the quality of the head assembly 30.
The present invention has been achieved in order to solve the aforementioned conventional problems. Accordingly, it is the primary object of the present invention to provide a jig and a method which eliminate the need for the inspector to change many times the position of the head assembly 30 at the time of making an appearance inspection in many directions.
Thus, according to the present invention, when carrying out the appearance inspection in many directions, only a series of operations for gradually raising the universal focus-adjusting lever upward are required, after the inspector first brings the upper-face image of the head assembly into focus with the focus adjusting handle. Therefore, the inspector can readily inspect the right side face, left side face, and front face of the head assembly without changing many times the position of the head assembly.
In addition, the present invention is capable of preventing damage due to the contact between the head assembly and objective lens in the course of inspection, destruction of the head assembly due to static electricity stored in the inspector""s body, and a reduction in the quality due to dirt on the head assembly, because the inspector does not directly hold the head assembly.
Furthermore, the present invention is capable of readily inspecting the lower face of the head assembly in addition to the right side face, left side face, and front face, by carrying out a series of operations for gradually raising the universal focus-adjusting lever upward , after the inspector first brings the upper-face image of the head assembly into focus with the focus adjusting handle.
Finally, the present invention is capable of easily inspecting the upper, right, left, and lower faces of the head assembly and also efficiently performing the operation of inspecting a plurality of head assemblies, because the inspector can set a plurality of head assemblies on the appearance inspecting jig at one time.
To attain the above-mentioned object, a jig is provided for inspecting the appearance of small parts with an optical microscope, comprising (1) a base, having an upper flat surface which becomes a mounting stage of the optical microscope, and also provided with a member for moving the upper flat surface at least in a direction approximately parallel to a direction of an optical axis of an objective lens of the optical microscope in order to focus the optical microscope on an inspection portion of the small parts mounted on the upper flat surface; and (2) an inspection-object supporting portion, provided with a member for supporting the small parts, which is mounted on the upper flat surface. The inspection-object supporting portion is provided with at least one reflecting mirror which has a mirrorlike surface with an inclined angle of approximately 45 degrees to the upper flat surface, the reflecting mirror being disposed on the inspection-object supporting portion in such a manner that the mirrorlike surface is positioned, facing one side face of the small parts so that an image of the one side face is reflected at the mirrorlike surface and visible within a visual field of the optical microscope.
The inspecting method of employing an appearance inspecting jig of the present invention is a method of inspecting the appearance of small parts with an optical microscope employing an appearance inspecting jig which comprises: a base, having an upper flat surface which becomes a mounting stage of the optical microscope, and also provided with a member for moving the upper flat surface so that the optical microscope is focused at a position of inspection of the small parts mounted on the upper flat surface; and an inspection-object supporting portion, provided with a member for supporting the small parts, which is mounted on the upper flat surface; the inspection-object supporting portion being provided with a reflecting mirror which has a mirrorlike surface with an inclined angle of approximately 45 degrees to the upper flat surface, the reflecting mirror being disposed so that at least one side face of the small parts and the mirrorlike surface of the reflecting mirror face each other. The method comprises the steps of: making an inspection with an upper face of the small parts moved to a focal position of the optical microscope, by employing the moving member; and inspecting the at least one side face of the small parts projected on the mirrorlike surface of the reflecting mirror, by employing the moving means.